ZCZC MIATCDAT3 ALL TTAA00 KNHC DDHHMM Tropical Storm Lorenzo Discussion Number 5 NWS National Hurricane Center Miami FL AL132019 1100 PM AST Mon Sep 23 2019 Infrared satellite imagery and microwave data indicate that convection and banding has been on the increase this evening very near the the center of Lorenzo, while the existing bands that extend well away from the center have been growing in size. This improving organization supports raising the initial intensity to 45 kt, and this is in agreement with the latest subjective Dvorak estimates from both TAFB and SAB. A recent ASCAT-C overpass sampled tropical-storm-force winds that now extend up to 80 n mi in the northern semicircle and suggested that the initial wind speed could be a little conservative. Lorenzo will be in an environment favorable for intensification for the next several days. And, given the recent increase in convection near the storm's center, there is now greater confidence that Lorenzo could become a hurricane by late tomorrow. If the near-term forecast trend verifies, then it will raise confidence that Lorenzo may become a major hurricane in the medium range. Only at the very end of the forecast period does it appear that the system will begin to encounter increasing shear and some drier air, which should limit any further strengthening. The official NHC wind speed prediction shows intensification a little faster than the last forecast through the first couple of days, but is near the previous advisory thereafter. This forecast is very close to the HFIP corrected-consensus HCCA. Lorenzo is moving westward at 13 kt. A strong mid-level ridge to the north of the cyclone will steer it generally westward to west-northwestward over the next few days. Late in the forecast period, a break in the ridge is forecast to develop between 40-45W, which should cause Lorenzo to turn to the northwest. The official NHC forecast is very close to the previous one, and near the tightly clustered consensus aids. FORECAST POSITIONS AND MAX WINDS INIT 24/0300Z 11.6N 26.7W 45 KT 50 MPH 12H 24/1200Z 12.1N 28.9W 55 KT 65 MPH 24H 25/0000Z 12.8N 31.5W 65 KT 75 MPH 36H 25/1200Z 13.4N 34.3W 75 KT 85 MPH 48H 26/0000Z 14.0N 37.0W 80 KT 90 MPH 72H 27/0000Z 16.1N 41.3W 90 KT 105 MPH 96H 28/0000Z 19.0N 44.2W 100 KT 115 MPH 120H 29/0000Z 22.0N 46.0W 100 KT 115 MPH $$ Forecaster Latto NNNN